1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __KERNEL_PRINTK__
3 #define __KERNEL_PRINTK__
6 #include <linux/init.h>
7 #include <linux/kern_levels.h>
8 #include <linux/linkage.h>
9 #include <linux/cache.h>
10 #include <linux/ratelimit_types.h>
12 extern const char linux_banner[];
13 extern const char linux_proc_banner[];
15 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
17 #define PRINTK_MAX_SINGLE_HEADER_LEN 2
19 static inline int printk_get_level(const char *buffer)
21 if (buffer[0] == KERN_SOH_ASCII && buffer[1]) {
24 case 'c': /* KERN_CONT */
31 static inline const char *printk_skip_level(const char *buffer)
33 if (printk_get_level(buffer))
39 static inline const char *printk_skip_headers(const char *buffer)
41 while (printk_get_level(buffer))
42 buffer = printk_skip_level(buffer);
47 #define CONSOLE_EXT_LOG_MAX 8192
49 /* printk's without a loglevel use this.. */
50 #define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
52 /* We show everything that is MORE important than this.. */
53 #define CONSOLE_LOGLEVEL_SILENT 0 /* Mum's the word */
54 #define CONSOLE_LOGLEVEL_MIN 1 /* Minimum loglevel we let people use */
55 #define CONSOLE_LOGLEVEL_DEBUG 10 /* issue debug messages */
56 #define CONSOLE_LOGLEVEL_MOTORMOUTH 15 /* You can't shut this one up */
59 * Default used to be hard-coded at 7, quiet used to be hardcoded at 4,
60 * we're now allowing both to be set from kernel config.
62 #define CONSOLE_LOGLEVEL_DEFAULT CONFIG_CONSOLE_LOGLEVEL_DEFAULT
63 #define CONSOLE_LOGLEVEL_QUIET CONFIG_CONSOLE_LOGLEVEL_QUIET
65 extern int console_printk[];
67 #define console_loglevel (console_printk[0])
68 #define default_message_loglevel (console_printk[1])
69 #define minimum_console_loglevel (console_printk[2])
70 #define default_console_loglevel (console_printk[3])
72 static inline void console_silent(void)
74 console_loglevel = CONSOLE_LOGLEVEL_SILENT;
77 static inline void console_verbose(void)
80 console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
83 /* strlen("ratelimit") + 1 */
84 #define DEVKMSG_STR_MAX_SIZE 10
85 extern char devkmsg_log_str[];
88 extern int suppress_printk;
97 * Add this to a message where you are sure the firmware is buggy or behaves
98 * really stupid or out of spec. Be aware that the responsible BIOS developer
99 * should be able to fix this issue or at least get a concrete idea of the
100 * problem by reading your message without the need of looking at the kernel
103 * Use it for definite and high priority BIOS bugs.
106 * Use it for not that clear (e.g. could the kernel messed up things already?)
107 * and medium priority BIOS bugs.
110 * Use this one if you want to tell the user or vendor about something
111 * suspicious, but generally harmless related to the firmware.
113 * Use it for information or very low priority BIOS bugs.
115 #define FW_BUG "[Firmware Bug]: "
116 #define FW_WARN "[Firmware Warn]: "
117 #define FW_INFO "[Firmware Info]: "
121 * Add this to a message for hardware errors, so that user can report
122 * it to hardware vendor instead of LKML or software vendor.
124 #define HW_ERR "[Hardware Error]: "
128 * Add this to a message whenever you want to warn user space about the use
129 * of a deprecated aspect of an API so they can stop using it
131 #define DEPRECATED "[Deprecated]: "
134 * Dummy printk for disabled debugging statements to use whilst maintaining
135 * gcc's format checking.
137 #define no_printk(fmt, ...) \
140 printk(fmt, ##__VA_ARGS__); \
144 #ifdef CONFIG_EARLY_PRINTK
145 extern asmlinkage __printf(1, 2)
146 void early_printk(const char *fmt, ...);
148 static inline __printf(1, 2) __cold
149 void early_printk(const char *s, ...) { }
152 struct dev_printk_info;
155 asmlinkage __printf(4, 0)
156 int vprintk_emit(int facility, int level,
157 const struct dev_printk_info *dev_info,
158 const char *fmt, va_list args);
160 asmlinkage __printf(1, 0)
161 int vprintk(const char *fmt, va_list args);
163 asmlinkage __printf(1, 2) __cold
164 int printk(const char *fmt, ...);
167 * Special printk facility for scheduler/timekeeping use only, _DO_NOT_USE_ !
169 __printf(1, 2) __cold int printk_deferred(const char *fmt, ...);
171 extern void __printk_safe_enter(void);
172 extern void __printk_safe_exit(void);
174 * The printk_deferred_enter/exit macros are available only as a hack for
175 * some code paths that need to defer all printk console printing. Interrupts
176 * must be disabled for the deferred duration.
178 #define printk_deferred_enter __printk_safe_enter
179 #define printk_deferred_exit __printk_safe_exit
182 * Please don't use printk_ratelimit(), because it shares ratelimiting state
183 * with all other unrelated printk_ratelimit() callsites. Instead use
184 * printk_ratelimited() or plain old __ratelimit().
186 extern int __printk_ratelimit(const char *func);
187 #define printk_ratelimit() __printk_ratelimit(__func__)
188 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
189 unsigned int interval_msec);
191 extern int printk_delay_msec;
192 extern int dmesg_restrict;
195 devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write, void *buf,
196 size_t *lenp, loff_t *ppos);
198 extern void wake_up_klogd(void);
200 char *log_buf_addr_get(void);
201 u32 log_buf_len_get(void);
202 void log_buf_vmcoreinfo_setup(void);
203 void __init setup_log_buf(int early);
204 __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
205 void dump_stack_print_info(const char *log_lvl);
206 void show_regs_print_info(const char *log_lvl);
207 extern asmlinkage void dump_stack_lvl(const char *log_lvl) __cold;
208 extern asmlinkage void dump_stack(void) __cold;
210 static inline __printf(1, 0)
211 int vprintk(const char *s, va_list args)
215 static inline __printf(1, 2) __cold
216 int printk(const char *s, ...)
220 static inline __printf(1, 2) __cold
221 int printk_deferred(const char *s, ...)
226 static inline void printk_deferred_enter(void)
230 static inline void printk_deferred_exit(void)
234 static inline int printk_ratelimit(void)
238 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
239 unsigned int interval_msec)
244 static inline void wake_up_klogd(void)
248 static inline char *log_buf_addr_get(void)
253 static inline u32 log_buf_len_get(void)
258 static inline void log_buf_vmcoreinfo_setup(void)
262 static inline void setup_log_buf(int early)
266 static inline __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...)
270 static inline void dump_stack_print_info(const char *log_lvl)
274 static inline void show_regs_print_info(const char *log_lvl)
278 static inline void dump_stack_lvl(const char *log_lvl)
282 static inline void dump_stack(void)
288 extern int __printk_cpu_trylock(void);
289 extern void __printk_wait_on_cpu_lock(void);
290 extern void __printk_cpu_unlock(void);
293 * printk_cpu_lock_irqsave() - Acquire the printk cpu-reentrant spinning
294 * lock and disable interrupts.
295 * @flags: Stack-allocated storage for saving local interrupt state,
296 * to be passed to printk_cpu_unlock_irqrestore().
298 * If the lock is owned by another CPU, spin until it becomes available.
299 * Interrupts are restored while spinning.
301 #define printk_cpu_lock_irqsave(flags) \
303 local_irq_save(flags); \
304 if (__printk_cpu_trylock()) \
306 local_irq_restore(flags); \
307 __printk_wait_on_cpu_lock(); \
311 * printk_cpu_unlock_irqrestore() - Release the printk cpu-reentrant spinning
312 * lock and restore interrupts.
313 * @flags: Caller's saved interrupt state, from printk_cpu_lock_irqsave().
315 #define printk_cpu_unlock_irqrestore(flags) \
317 __printk_cpu_unlock(); \
318 local_irq_restore(flags); \
323 #define printk_cpu_lock_irqsave(flags) ((void)flags)
324 #define printk_cpu_unlock_irqrestore(flags) ((void)flags)
326 #endif /* CONFIG_SMP */
328 extern int kptr_restrict;
331 * pr_fmt - used by the pr_*() macros to generate the printk format string
332 * @fmt: format string passed from a pr_*() macro
334 * This macro can be used to generate a unified format string for pr_*()
335 * macros. A common use is to prefix all pr_*() messages in a file with a common
336 * string. For example, defining this at the top of a source file:
338 * #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
340 * would prefix all pr_info, pr_emerg... messages in the file with the module
344 #define pr_fmt(fmt) fmt
348 * pr_emerg - Print an emergency-level message
349 * @fmt: format string
350 * @...: arguments for the format string
352 * This macro expands to a printk with KERN_EMERG loglevel. It uses pr_fmt() to
353 * generate the format string.
355 #define pr_emerg(fmt, ...) \
356 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
358 * pr_alert - Print an alert-level message
359 * @fmt: format string
360 * @...: arguments for the format string
362 * This macro expands to a printk with KERN_ALERT loglevel. It uses pr_fmt() to
363 * generate the format string.
365 #define pr_alert(fmt, ...) \
366 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
368 * pr_crit - Print a critical-level message
369 * @fmt: format string
370 * @...: arguments for the format string
372 * This macro expands to a printk with KERN_CRIT loglevel. It uses pr_fmt() to
373 * generate the format string.
375 #define pr_crit(fmt, ...) \
376 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
378 * pr_err - Print an error-level message
379 * @fmt: format string
380 * @...: arguments for the format string
382 * This macro expands to a printk with KERN_ERR loglevel. It uses pr_fmt() to
383 * generate the format string.
385 #define pr_err(fmt, ...) \
386 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
388 * pr_warn - Print a warning-level message
389 * @fmt: format string
390 * @...: arguments for the format string
392 * This macro expands to a printk with KERN_WARNING loglevel. It uses pr_fmt()
393 * to generate the format string.
395 #define pr_warn(fmt, ...) \
396 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
398 * pr_notice - Print a notice-level message
399 * @fmt: format string
400 * @...: arguments for the format string
402 * This macro expands to a printk with KERN_NOTICE loglevel. It uses pr_fmt() to
403 * generate the format string.
405 #define pr_notice(fmt, ...) \
406 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
408 * pr_info - Print an info-level message
409 * @fmt: format string
410 * @...: arguments for the format string
412 * This macro expands to a printk with KERN_INFO loglevel. It uses pr_fmt() to
413 * generate the format string.
415 #define pr_info(fmt, ...) \
416 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
419 * pr_cont - Continues a previous log message in the same line.
420 * @fmt: format string
421 * @...: arguments for the format string
423 * This macro expands to a printk with KERN_CONT loglevel. It should only be
424 * used when continuing a log message with no newline ('\n') enclosed. Otherwise
425 * it defaults back to KERN_DEFAULT loglevel.
427 #define pr_cont(fmt, ...) \
428 printk(KERN_CONT fmt, ##__VA_ARGS__)
431 * pr_devel - Print a debug-level message conditionally
432 * @fmt: format string
433 * @...: arguments for the format string
435 * This macro expands to a printk with KERN_DEBUG loglevel if DEBUG is
436 * defined. Otherwise it does nothing.
438 * It uses pr_fmt() to generate the format string.
441 #define pr_devel(fmt, ...) \
442 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
444 #define pr_devel(fmt, ...) \
445 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
449 /* If you are writing a driver, please use dev_dbg instead */
450 #if defined(CONFIG_DYNAMIC_DEBUG) || \
451 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))
452 #include <linux/dynamic_debug.h>
455 * pr_debug - Print a debug-level message conditionally
456 * @fmt: format string
457 * @...: arguments for the format string
459 * This macro expands to dynamic_pr_debug() if CONFIG_DYNAMIC_DEBUG is
460 * set. Otherwise, if DEBUG is defined, it's equivalent to a printk with
461 * KERN_DEBUG loglevel. If DEBUG is not defined it does nothing.
463 * It uses pr_fmt() to generate the format string (dynamic_pr_debug() uses
464 * pr_fmt() internally).
466 #define pr_debug(fmt, ...) \
467 dynamic_pr_debug(fmt, ##__VA_ARGS__)
469 #define pr_debug(fmt, ...) \
470 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
472 #define pr_debug(fmt, ...) \
473 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
477 * Print a one-time message (analogous to WARN_ONCE() et al):
481 #define printk_once(fmt, ...) \
483 static bool __section(".data.once") __print_once; \
484 bool __ret_print_once = !__print_once; \
486 if (!__print_once) { \
487 __print_once = true; \
488 printk(fmt, ##__VA_ARGS__); \
490 unlikely(__ret_print_once); \
492 #define printk_deferred_once(fmt, ...) \
494 static bool __section(".data.once") __print_once; \
495 bool __ret_print_once = !__print_once; \
497 if (!__print_once) { \
498 __print_once = true; \
499 printk_deferred(fmt, ##__VA_ARGS__); \
501 unlikely(__ret_print_once); \
504 #define printk_once(fmt, ...) \
505 no_printk(fmt, ##__VA_ARGS__)
506 #define printk_deferred_once(fmt, ...) \
507 no_printk(fmt, ##__VA_ARGS__)
510 #define pr_emerg_once(fmt, ...) \
511 printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
512 #define pr_alert_once(fmt, ...) \
513 printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
514 #define pr_crit_once(fmt, ...) \
515 printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
516 #define pr_err_once(fmt, ...) \
517 printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
518 #define pr_warn_once(fmt, ...) \
519 printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
520 #define pr_notice_once(fmt, ...) \
521 printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
522 #define pr_info_once(fmt, ...) \
523 printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
524 /* no pr_cont_once, don't do that... */
527 #define pr_devel_once(fmt, ...) \
528 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
530 #define pr_devel_once(fmt, ...) \
531 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
534 /* If you are writing a driver, please use dev_dbg instead */
536 #define pr_debug_once(fmt, ...) \
537 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
539 #define pr_debug_once(fmt, ...) \
540 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
544 * ratelimited messages with local ratelimit_state,
545 * no local ratelimit_state used in the !PRINTK case
548 #define printk_ratelimited(fmt, ...) \
550 static DEFINE_RATELIMIT_STATE(_rs, \
551 DEFAULT_RATELIMIT_INTERVAL, \
552 DEFAULT_RATELIMIT_BURST); \
554 if (__ratelimit(&_rs)) \
555 printk(fmt, ##__VA_ARGS__); \
558 #define printk_ratelimited(fmt, ...) \
559 no_printk(fmt, ##__VA_ARGS__)
562 #define pr_emerg_ratelimited(fmt, ...) \
563 printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
564 #define pr_alert_ratelimited(fmt, ...) \
565 printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
566 #define pr_crit_ratelimited(fmt, ...) \
567 printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
568 #define pr_err_ratelimited(fmt, ...) \
569 printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
570 #define pr_warn_ratelimited(fmt, ...) \
571 printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
572 #define pr_notice_ratelimited(fmt, ...) \
573 printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
574 #define pr_info_ratelimited(fmt, ...) \
575 printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
576 /* no pr_cont_ratelimited, don't do that... */
579 #define pr_devel_ratelimited(fmt, ...) \
580 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
582 #define pr_devel_ratelimited(fmt, ...) \
583 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
586 /* If you are writing a driver, please use dev_dbg instead */
587 #if defined(CONFIG_DYNAMIC_DEBUG) || \
588 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))
589 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
590 #define pr_debug_ratelimited(fmt, ...) \
592 static DEFINE_RATELIMIT_STATE(_rs, \
593 DEFAULT_RATELIMIT_INTERVAL, \
594 DEFAULT_RATELIMIT_BURST); \
595 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt)); \
596 if (DYNAMIC_DEBUG_BRANCH(descriptor) && \
598 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \
601 #define pr_debug_ratelimited(fmt, ...) \
602 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
604 #define pr_debug_ratelimited(fmt, ...) \
605 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
608 extern const struct file_operations kmsg_fops;
615 extern int hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
616 int groupsize, char *linebuf, size_t linebuflen,
619 extern void print_hex_dump(const char *level, const char *prefix_str,
620 int prefix_type, int rowsize, int groupsize,
621 const void *buf, size_t len, bool ascii);
623 static inline void print_hex_dump(const char *level, const char *prefix_str,
624 int prefix_type, int rowsize, int groupsize,
625 const void *buf, size_t len, bool ascii)
628 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
629 const void *buf, size_t len)
635 #if defined(CONFIG_DYNAMIC_DEBUG) || \
636 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))
637 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
638 groupsize, buf, len, ascii) \
639 dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
640 groupsize, buf, len, ascii)
642 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
643 groupsize, buf, len, ascii) \
644 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize, \
645 groupsize, buf, len, ascii)
647 static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type,
648 int rowsize, int groupsize,
649 const void *buf, size_t len, bool ascii)
655 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
656 * @prefix_str: string to prefix each line with;
657 * caller supplies trailing spaces for alignment if desired
658 * @prefix_type: controls whether prefix of an offset, address, or none
659 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
660 * @buf: data blob to dump
661 * @len: number of bytes in the @buf
663 * Calls print_hex_dump(), with log level of KERN_DEBUG,
664 * rowsize of 16, groupsize of 1, and ASCII output included.
666 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \
667 print_hex_dump_debug(prefix_str, prefix_type, 16, 1, buf, len, true)